Stem cell cryopreservation.

The recent widespread use of protocols, including high dose chemotherapy with peripheral blood progenitor cell rescue, has resulted in increased demand for cryobiological services to freeze and thaw the collected progenitors. This has led to reexamination of many cryobiological practices and proposal of alternative methodologies. This review examines the scientific bases of cryobiological practices, how cryoprotectants work and alternative methods of freezing and thawing. Finally, while blood banks have come under tremendous regulatory pressure from federal agencies, hematopoietic stem cell processing has been relatively unburdened by such regulation to date. Recent meetings between the FDA and interested organizations make it clear that this largesse is coming to an end. Hence many organizations are promulgating standards that apply to marrow and peripheral stem cell processing.